Electric signaling apparatus.



L. W. CARROLL. ELECTRIC SIGNALING APPARATUS.

Y APPLICATION FILED JULY 16, 1906..

Patented May 17, 1910.

Y 3 SHEETS-SHEET 1.

a. l n.

L. W. CARROLL;-

ELEGTRIG SIGNALING APPARATUS.

APPLICATION FILED JULY 16,1906.

Patented May 1?, 1910.

3 SHEETS-SHEET 2.

LOUIS W. CARROIL, OF ANAMQSA, IOWA.

ELECTRI SIGNALING APPARATUS;

Specification of LetterslPatent.

Appiieauon tied July is, 190e. seriaim. 326,430.

To ull lwhom it 'may concern.'

Be it known that I, Louis W. CARROLL, a #citizen vof the United States,and resident of Anamosa, county-olf Jones, and Staate y.olf

rality I'of stations all served by a single sig-'1 nal lineWithout'giving any perceptible indication at any lof the 'otherstationsupon the iline that one of them is being called.

The invention has for its 4object `:to pro- -vide an improved electricsignal, and especially to make. it possible to signal any one of a largenumber of stations,r all-of which are upon the saine electric circuit orline, bythe selective method.

The apparatus provided by the invention will -ordinarily be used inconjunction with the so-called jparty line ltelephone apparatus, andwill then preferably include at 'each telephone station or instrumentupon the line an electric signal comprising an acoustic vibratile body,such for example as the wellknown timing fork, that for each stationupon the line having a di'erent tone or period of vibration,'and anelectro-magnet for vibrating the acoustic body. At the central stationthere will then be provided,

means for sending 'over `the line a pulsating or alternating electriccurrent having -a :frequencyvequa'l to or in harmony with the period ofvibration of the signal at any one of the line stations, and which'therefore will actuate the signal at that particular station withoutappreciably affecting any of the others. y

To increase the intensit of the signal there will usually be provided,at -each of the line stations, some form of resonator, and this willlmost convenientlytake lthe form of an open-ended tube or pipe, themouth of which Will be placed adjacent the vibratile body of Vthesignal. This form of 5resonator maybe tuned to respond only to theprincipal tone or any-definite harmonic tone-of the signal, and mayserve, therefore, to lncrease the range of tone which ina-y be ratus .ofthe invention, while any vibrations produced in thesignalto which it isapplied, other `.than those of v-the tone "to Awhich the' resonator-istuned, will -not 4be rendered zaudi- 'ble thereby.

In 4the preferred yform of embodiment of theinventionfthe apparatus at`the central, station for sending a pulsating l.or alternating electriccurrent over the lil-1e includes some source of lelectric energy, as :astorage battery, :and .a plurality of variable resistance devices eachcontrollediby .a vibratile body which is tuned in harmony with that ofvthe signal at one of 'the line stationsf The apparatus Lat `the sendingstation also includes an electro-magnet 'for actuating 'each l of thevibratile bodies at thatstation,

and in order that the apparatus for signaling each stationmay beoperated independently of those for signaling other stations, theelectro-magnet and variable resistance device of each part ofthe sendingapparatus are in a branch of the line circuit, and each of these circuit.branches vhas a switch, normally open, 'but which may be closed 'tocomplete the line circuit through the `particular branch which itcontrols. i

In the accompanying drawings, Figure 1- is a diagrammatic illustrationof one form o apparatus constructedaccording Ito the invention; Fig. 2shows-a detail ofthat part of the apparatus which will commonly belocated at the central or sending station, some of the parts bein shownin vertical section, as indicated by the line 2-2 of Fig. 3, and otherparts bein shown in diagram; Fig. 3 is a plan View o the parts shown inFig. 2; Fig. 4 shows a modiied form of sending a paratus; Fig. '5 is aVertical section on vt e line 5+5 of F ig.4=; Fi '6 is a centralvertical section of the pre erred form of si nal to be llocated at eachof the line stations.;l ig. `7 is a plan yiewv on the line 7 7 of Fig.6; Fig. 8 is a plan view of a modied forni of signal; Fig. 9 is a sideelevation, partly in section, of the same; Fi 10' is a side elevation,partly in section, o a still further modied form oflsignal; Fig. 11 is aplan View of the same; Fig. 12pi-s similar to Fig. 2 but showing amodified form of sending apparatus; Fig. 13 is a'plan View of certainparts shown in Fig. 12.; and Fig. 14 illustrates 4in diagram a modifiedyarrangement of fthe apparatus. l

Patented May 17,1910.

practically produced .by the signaling appa iii/0 Y v socket, and bymeans of this switch the line There is shown in Fig. 1 of the drawings aform of signaling apparatus comprising a central or sending stationand'three receiving stations, all upon the same line or electric circuitand any one of which maylbe called without indicating that fact ateither of the others. That part of the apparatus line 26, being dividedat -27 into branches 28,

29, 30, one for each station to bev called, and reuniting at 31. In eachof the branches 28, 29, 30, there is a switch 32, shown as taking theform of the common telephone plug and circuit may be closed through theparticular branch. which it controls. There is also in each of thecircuit branches a. sending instrument 33,'shown in-detail in Figs. 2and 3 of the drawings, and at each of the line stations, as 34, 35, formof which is clearly shown in Figs. 6 and 7. Each of the signals 37 ispreferably bridged or shunted into the line cir-l cuit, as indicated atthe upper portion of Fig. 1, and the .current most conveniently returnsto the sending station through the earth, grounded terminals beingprovlded at 38 and 39 for that purpose. V

For each of the sending instruments 33 there is preferably provided abase or stand-y ard 40 (Fig. 2), having, as shown, a yoke .45 from whichis suspended an electro-magnet'44. For lthe armature of the magnet thereis provided a vibr'atile body, such as the reed 43, and this ispreferably secured to a vertical portion 41 of the base 40 by a bolt42.A The reeds 43 of the several instruments 33 have a different periodof vibration or tone, this being preferably accomplished by making eachof a different length, as clearly shown lin Fig. 1. 7

A variable resistance device 46 is also mounted upon the base 40 of eachof the sending instruments, and preferably this device is of-that formin. which an electric current is caused to traverse a quantity ofgranulated. carbon', the resistance to the passage of the current beingvaried by causing the particles of carbon to become more or lesscompacted by pressure.

As shown the variable resistance device 46 comprises a tubular casinghaving. its ends closed by diaphragms 47 48, secured in (place by meansof threadedcap rings 49,

upon the inner face of'each of the diaphragms there is a carbon disk 50.Each of the dlaphra s 47 48, is also provided with 36, there is a signal37, one.

an outward y extending threaded stem 51,'

52,'the lower one of-which is .secured to the base 40 and serves as asupport for the device, while the upper one 52 connects with `the reed43. A quantity of granulated carbon 53 is inclosed within thevariable'resistance device between the two diaphragms 47, 48, andbecomes more or less compacted by relative movement of the twodiaphragms caused by the vibration of the reed 43.

I n order that the connection between the threaded stem 52 of one of thediaphragms of the variable resistance device and the reed may not serveas a fulcrum as the latter vibrates, thus permitting Ythe reed to'buckle between this connection and its support, it is preferably maderigid for a portion of its length by the application thereto of areinforcin plate 54. This reinforcing plate extends rom the point ofconnection of the threaded stem 52 `for a considerable distance' towardthe support 41, leaving a short section of the reed next adjacent thesupport'free to flex as an elastic hinge when v the reed is vibrated.

One of the branches, as 28, of the line circuit is caused to traversethe variable resistance device 46 and the electro-magnet 44 of each ofthe sending instruments, and as shown is connected with one of thethreaded #stems 51 of the variable resistance device at 55, with thereed (which has electrical connectlon with the other threa'ded stem '52of l the variable resistance device) at 56, and with the two terminalsof the electro-magnet 44 at 57 and '58.` v

For the signal appar tus 37 Yat each of the line stations 34, 35, 36,there is provided a suitable base 59, preferably taking the form of awall plate to beapplied to the face of a telephone instrument. rllheapparatus of each f the signals comprises an acoustic vibratile body, asthe reed 60, having one of its ends rigidly secured to the base 59 by abolt 61 and an electro-magnet`62 carried by the base 59 in such positionthat one of its poles is adjacent the freeI end of thereed 60. Throughthe coils 63 of this electro-magnet 'the line circuit 26 is caused topass, the magnets of 'the signals at the various stations beingpreferably connected 'to the'line in a shunt or bridg In order toincrease the intensity of the signal at each station, there ispreferably provided, for the reed 60 some form of resonator, and asshown in Figs. 1, 6 and 7 of the drawings this takes the form of anopenended tube 64, carried, by a'Joracket-arm 65 of the base 59, in sucha positionv that its mouth 66 v is adjacent the free end of the reed 60.This resonator may be of proper size to respond to the principal tone oranyharmonic tone of the .reed 60 when vibrated, and magnies the sound ofthe vibrating reed to produce a signal of considerable intensity.

the-

esami 11n practice, if the device is :to be .used in conjunction withtelephone apparatus, the storage batteries 24 or other generator, fthesending vinstruments 33 and the switches :32 wiiill :be ilocated in anyconvenient posit-ion at the telephane [central station, the switches 32preferably forming .a part od. the operating :switch board, not shown,of the telephone system, while the signal line 26 :and the severalsignals 3.7 will be incorporated with :the telephone lime fand its'various instruments. When not in use the circuit will be open at eachof'theifswitches 32, and whenever a given station is to Kbelcalled itheswitch of the lbranch of the circuit 28, 29er 30 shaving a sendinginstrument 33, the -vibratile body 43 of which is tuned in harmony withthe `v-ibratile body 60 of the station to be called, will be closed,thereby completing the circuit through that branchvand lits sendinginstrument. p

The flow of current from the storage batteries 24 Avitalizes the magnet44 of the sending instrument a d the magnets 62 of'all of the yreceivingi ruments, causing them to attract the vibratile reeds 43 and 60,respeotively. The raising ofthe -reed 43 raises the diaphragm 47 of 'thevariable resistance device 46 and :increases the resistance to the ow ofcurrent by reducing the pressure upon the quantity of granulated carbon53 contained therein. 'llhis weakens the flow of current through :theline, -zpermitting th`e vibratile reeds 43 and 60, owing to theirelasticity, to fall -away from the magnets of the sending and receivingstations. The lowering ofthe .reed 43 immediately diminishes theresistance tothe flow of current by means of the increased pressure uponthe upper diaphragm of the yvariable resistance device, and the-magnetsare again suiiiciently vitalized to attract the reeds 43 and which theycontrol. In this way a rapid vibration lof the reed 43 is produced and acorresponding vibration is also produced inA Athe reed 60 of that one ofthe signals 37 Whichis of the .proper tone to vibrate with it, itheothers, lbeing incapable of vibrating at the same rate, are butlittleaffected.

The Avibration .of thereed 60 of t-he vrecci-.ving 'instrument or signal37 is immediately .communicated to the column of air by the sending`instruments 33 :may `.he 'p caused-to :flow through the line of 'thereceiving .instruments by `the :use .of an ind-uction coil,-diagrammatically indicated .at 67.,

14. The dine .circuit 68 then constitutes the lsecondary .circuit ofthe4induction coil and `is preferably ,provided with ground terminals 69and 70, vwhile the circuit ,26 including .the storage batteries 24 :andthe eendingv instruments 33 constitutes the Aprimary circuit of :theinduction coil, a return wire 7l, leading tol the batteries, beingpreferably substituted for the ground fterlninals 38, 39 of 1.

Other forms of vibratile bodies .capable of vibrating kat a sulicientrate -to produce musical tones may be employed .in Vfthe apparatus, and.in Figs. l0 and 11 of the drawings there is illustrated a receivinginstrument vor lsignal having a metallic string or cord 72, ystretchedover ay bridge 72a by means of a tuning key 73. A resonator in the formof a sounding board 74 is preferably incorporated `with vthis form ofreceiving signal, andthe same A`form lof resonator lmay vbe employed inconnection with a signal comprislng a vibratile reed 76, as shown in 4Fig. 9. When a soundingvlboard is emloyed, as a resonator, anelectro-magnet 75 is vsupported over the board to actuate the -vibratilebodyof the signal, and is carried by a bracket-arm 77 rising from one'ofa pair offsuitable standards 78, which also support the soundingboard.

It may be desirable in. some instances .to incorporate in a singlesending instrument 33 a plurality of variable ,resistance devices of theform shown in Figs. 2 and 3, all of which may be simultaneously actuatedfrom the vibratile reed 43 of the instrument. sending instrument 4ol"Athis form :is illus-y trated :in Figs. 4 and 5, and in Fig.- 14 of thedrawingsi Though moredesirable .than a sending instrument 'having but a.lslngle variable resistance device, it 1s :notessential to theoperation of the form of apparatus including the induction coil -67shown in Fig. 14, and has been added to :that figurey merely ffor thepurpose of illustration. In

this-form of sending instrument, vas shown, the vibratile reed 43 is.provided with a cross-arm .79, and .a yplural-ity Aof `wiriable diatelybelow the cross-arm, the upper threaded stem 52 of these devices being`directly connected thereto. The electric current is then led to theinstrument through the Wire 25 connected to the stem 51 of one Fof thevariable resistance devices at 55, and is caused to traverse the severaldevices in series, as' most clearly shown in Fig. 5, being led from thatone at the left as viewed in 'that figure to the one at the eXtremeright, through the cross-arm 79 which is insulated from the stem 52 ofthe variable resistance device 81 and from the reed 43 by means ofwashers 83, 84 of non-conducting material, and passesA from the stem 51of the variable resistance device 82 to the corresponding stem of thelvariable resistance device 81 through a suitable connection 85 andthrough that device to the reed 43, as inthe form of vconstructionillustrated in Figs. 2 and 3.

In Figs. 12 and 13 there is illustrated a form of sending instrumenthaving a resonator 86 in the form'of a sounding board. This resonator issupported by suitable standards from a base 87, and an electromagnet 88is carried by a bracket-arm 89 rising from the same base and occupies av proper'position over the sounding board for actuating a vibratilelreed 90, mounted on the board. v; A variable resistane device 9 1 ofthe form illustrated in Figs. 2 and3, 1s

mounted on the base below the board. It is mechanically connected to thesounding board by means of of its diaphragms, as 47, and is electricallyconnected to the vmagnet 88 by means of a conducting Wire 93 leadingfrom the bolt 92 tothe magnet. In this form of instrument 'the operationof the variable resistance device is directly effected by the vibrationof the sounding board rather than by that of the vibra-tile reed, whilethe sounding board serves further as aresonator to intensity the soundof the vibratile reed, and the instrument therefore is of a desirableform for use as a signal without other apparatus.

As a single electric wire is capable v of l simultaneously transmittingcurrents having different periods of vibration or phases, more than oneof the signals 37 may be vsimultaneously operated by closing the switch32 ofmore than one of the branches 28, 29, 30 at the same time. Theapparatus is therefore capable of use for the purpose of sending aplurality of signals of diierent character over a single line at onetime.

\ tro-magnet, a tuned The apparatus may also be used as a musicalinstrument.

I claim as my invention- 1. In combination with an electricircuit havinga generator, a variable resista ce device, and atransmitting and areceiving elecvibratile armature for the transmitting electro-magnetoperatively connectedv to the vari ble resistance device,

a bolt 92 rising from oneA and a vibratile armature for the receivingelectro-magnet tuned in harmony with the rst-named armature.

2. In combination with an electric circuit having a generator, avariable resistance device, and a transmitting and a receivingelectro-magnet, a tuned vibratile armature for the transmittingelectro-magnet operatively connected to the variable resistance device,a vibratile armature for the receiving electro-magnet tuned in, harmonywith the first-named armature, and a resonator for the second-namedarmature.

3. In combination, a generator, a trans` mitting and a receivingelectro-magnet served by the generator, a variable resistance device incircuit with the coils of the transmitting electro-magnet, a tunedvibratile armature for the transmitting electro-magnet operatively'connected to the variable resistance device, and a vibratile armaturefor the receiving electro-magnet tuned in harmony with the first-namedarmature.l e

4. In lcombination, a generator, a plurality of transmitting andreceiving electro-magnets served by the generator, a variable resistancedevice in circuitwith the coils of each of the transmittingelectro-magnets', av

tuned vibratile armature for each of the transmitting electro-magnetsoperatively connected to the variable resistance device in circuit withthe coils of such magnet, the

armatures being of differing pitch, and a vibratile armature for each ofthe receiving electro-magnets, each one of such armaturesbeing tuned inharmony with a separate one of the armatures of the transmittingelectromagnets. f

5. In combination, a primary electric circuit having a generator, avariable resistance device, and an electro-magnet, a tunedvibra- 4.tiled armature for the electro-magnet operatively connected with thevariable resistance device, av secondary circuit having anelectromagnet, and a vibratile yarmature for the last-namedelectro-,magnet tuned in harmony with the first-named' armature.

'6. In combination, a primary electric circuit having a generator, avariable resistance device, and an electro-magnet, a tuned vibratilearmature for the electro-magnet operatively connected with the variableresistanceA device, a secondary circuit having an'electro-magnet, avibratile armature for the electro-magnet of the secondary circuit tunedin harmony with 1the first-named armature, and a resonator for thesecond-named armature. l 7 .,.In combination, a primary electriccircuit) having agenerator and a plurality of parallel branches, anelectro magnet, a switch and a variable resistance device in each ofvthe branches, a tuned vibratile armature for the electro-magnet of each`of the branches ofthe circuit operatively connected with the variableresistance device of the same branch of the circuit, the pitch of eachof the armatures being diierent from thatof havin a variable resistancedevice comprising a all of the others, a secondary electric circuithaving a plurality of electro-magnets, and a vibratile armature for eachof the electromagnets of the secondary circuit, each of such armaturesbeing tuned in harmony with one of the nist-named armatures.

8. In combination, a Vprimary electric circuit having a generator and aplurality of parallel branches, an 1' electro magnet, a switch and avariable resistance device in each of the branches, a tuned vibratilearmature for the electro-,magnet of each of the branches ofthe circuitoperatively'connected with the variable resistance device of the samebranchl of the circuit, the pitch of each of the armatures beingdiferent from that of all of the others, a secondary electric ciry cuithaving a plurality of electro-magnets, a

' variable resistance devices.

vibratile armature for each ofthe electromagnets of the secondarycircuit, each of such armatures being tuned in harmony with one of thefirst-named armatures, and a resonator for each of the second-namedarmatures.

9. In combination, a Xed support, a tuned vibratile reed having anelastic hinged connection with the fixed support and a rigid bodyportion, anf electric variable resistance device, operative connectionbetween the variable resistance device and a rigid portion of thevibratilev reed, an electro-magnet acting upon the reed, and electrical-connection'between the coils of the electro-magiiet and the variableresistance device. n

10. In combination, a fixed support, a vtuned vibratile reed having anelastic hinged connection with the fixed support and a rigid bodyportion, an electric'variable resistance device comprising a movablediaphragm connected by a `bolt to a rigid portion of the vibratilereed,an electro-magnet acting upon the reed, and'electrical connectionbetween the coils of the electro-magnet and the variable resistancedevice. y

11. In combination, a tuned vibratile body of magnetizable material, aplurality of electric lvariable resistance devices, operative connectionbetween the vibratile body and each of the variable resistance devices,an electro-magnet acting upon the vibratile body, and electricalconnection between the coils of the 'electro-magnet and all of the 12.In combination, a tuned vibratile body of magnetizable material, a`plurality of electric variable resist-ancekdevics e h comprising amovable diaphra m having operative connection with the vibratile body,an electro-magnet acting upon the vibratile body', and electricalconnection between the coils of the electrofmagnet and' all of thevariable resistance devices. v

13. In combination, an electric circuit a generator, an electro-magnetand movable diaphragm, and a timed vibratile armature for theelectro-magnet operatively connected to the movable diaphragm of thevariable resistance device.

14. In combination, an electric circuit having a. generator, anelectro-magnet and a plurality of variable resistance devices eachcomprising a movable diaphragm, and a tuned vibratile armature forthe'electromagnet having a cross-arm connected by `a bolt to the movablediaphragm ofeach of the variable resistance devices. Y

15. In combination, a fixed support, a tuned vibratile reed having an'elastic hinged connection with the fixed support and a rigid bodyportion, a cross-arm on the rigidbody portion of the reed, a pluralityof electric variabll resistance devices each comprising a movablediaphragm connected by a bolt to ,the cross-arm of the reed, anelectromagnet acting upon the reed, and electrical connection betweenthe coils of ,the electro magnet and all of the variable resistancedevices. f

16. In combination, a generator, a plurality of transmitting andreceiving electromagnets served by the generator, a variable resistancedevice and a switch in circuit with the coils of each of thetransmitting electromagnets, a tuned vibratile armature for each' of thetransmitting electro-magnets operatively connected to the variab eresistance device in circuitwith the coils of such inagnets, thearmatures being of differing pitch, and a vibratile armature for each ofthe receiving electro-magnets, each one of such armatures being tuned inharmony lwith a transmitting electro-magnet, and a pluralityv ofreceiving electro-magnet armatures, each one of'such armatures beingtuned in harmonywith a separate one of the transmity ting,velectro-magnetI armatures. 18. In combination, a branching electriccircuit having agenerator and an electromagnet, a plurality of variableresistance devices each in a branch of the circuit, a plurality of tunedvibratile electro-magnet i armatures of diiering pitch, and operativevices each connection between each of such armatures and one of thevariable resistance devices. 19. In combination, a branching electriccircuit having a generator and an electromagnet, a plurality of variableresistance de in a'branch of the circuit and each comprising a movablediaphragm, a p1u` rality of tuned vibratile4 electro-magnet armaturesofd diering pitch, and operative connection between each of sucharmatures and the diaphragm of one ofthe variable resistance devices.

20. In combination, an electric circuit having a generator, anelectro-magnetand a` variable resistance device comprising a xed and amovable diaphragm, and arvibratile armature for the electro-magnetoperatively i connected tothe movable diaphragm'of the variableresistance device.-

21. In combination, a generator, a plurality of variable resistancedevices, a plu! rality of switches, an electro-magnet served from thegenerator and'having its coils in circuit with each of the variableresistance devices and one of the switches, a'plurality of tunedvibratile electro-magnet armatures ofl ditl'ering pitch, and operativeconnection between each one of such armatures and a separate one of thevariable resistance devlees.

Louis W.- CARROLL;

' =Witnessesz p CHABms B. GrLLsoN, Louis KoGrnmsoN.

